farm2.static.flickr.comLyme grass is being found in the coastal dunes in Muskegon, Ottawa and Allegan counties, according to a new report prepared for The Nature Conservancy. The plant concerns botanists because it competes with native marram grass, or dune grass.

An invasive plant that competes with native dune grass is thriving at several sites along the Lake Michigan coast, but one expert said it's not too late to eradicate the troublesome species.

Lyme grass is flourishing at 125 sites in the coastal dunes in Muskegon, Ottawa and Allegan counties, according to a new report prepared for The Nature Conservancy. The plant concerns botanists because it competes with native marram grass, or dune grass — one of the predominant species in Great Lakes coastal dunes.

Left unchecked, lyme grass could spread across the dunes and — in the worst-case scenario — displace all native dune grass. No one knows how fields of lyme grass would affect the dune ecosystem, but some experts fear it could cause subtle but significant changes in plant, insect and animal communities.

"There are many more occurrences of lyme grass than we want to see along this stretch of coastline ... but it's early enough in the infestation that we can do something about it," said John Legge, West Michigan conservation director for The Nature Conservancy's Michigan chapter.

"I think there is enough interest in our sand dunes and invasive species that the situation with lyme grass is fairly hopeful," Legge said.

Lyme grass is far more prevalent in the coastal dunes in Indiana and Wisconsin.

The invasive grass is native to the sandy coasts of Europe. It is one of 900 nonnative plants in Michigan but the only one known to compete directly with marram grass for survival in the harsh, sand-swept environment of Great Lakes dunes.

Lyme grass is one of at least 13 invasive species of plants and trees living in coastal dunes in Muskegon, Ottawa and Allegan counties, according to William Martinus, who conducted the plant survey for The Nature Conservancy.

The survey of 75 miles of dunes in West Michigan last summer found lyme grass growing at 17 sites in Muskegon County, 65 in Ottawa County and 43 in Allegan County. The plants, which resemble dune grass but have thick, blue-green blades and rigid seed stalks, were found at the following public parks:

Lyme grass was found at several other sites on private property, Legge said.

It's possible to control the spread of lyme grass by spraying it with an herbicide. Such treatments are risky, however, because the chemical that kills lyme grass also kills native dune grass, Martinus said in his report.

It's nearly impossible to eliminate lyme grass without using herbicides.

"In most instances, removal of (lyme) grass is only temporary, as it will usually regenerate from nearby rootstock," Martinus said in the report.

Legge said efforts to remove lyme grass from area dunes could begin as early as next summer. He said the foreign plants must be removed soon to keep them from spreading and becoming the dominant species.

One invasive plant species found locally, spotted knapweed, is so widespread there is no chance of purging it from the dunes, Legge said.

Another troublesome invader, tall baby's breath, was found in the Kitchel-Lindquist Dune Preserve in Grand Haven. That plant species has colonized vast areas of dunes at the Sleeping Bear Dunes National Lakeshore near Traverse City. The federal government has spent thousands of dollars trying to control its spread.

Legge said West Michigan has a narrow window of opportunity in which to keep invasive plant species in check in the coastal dunes.

"Invasive plants are a serious problem in our open dunes, but it's one that we have an opportunity to manage and keep from getting out of control," Legge said. "The situation here is a lot better than it is up north."